Tons operating safety



April 19.1927. 1,625,528

, W. C. ERWIN ET AL TONG OPERATING SAFETY APPLIANCE Filed April 27. 1325 INVENTORS. WELDON CIRWIN CECIL H. SWEET A TTORNEY.

Patented Apr. 1S), 1927.

UNITE W'ELDON C. ERWIN, D1? YORBA LINDA, AND GECIL H. SWEET, Ola" BREA, CALIFORNIA, ASSIGNORS TO JOHN Hf. IvIAoCIiATCHIE, G COMPTON, CALIFORNIA.

TONG OPERATING SAFETY APPLIANCE.

Application filed April 27, 1925.

This invention is a safety appliance for operating the tongs which are used in setting up or unscrewing the joints of well casing or drill stem.

it is the object of the invention to utilize the rotary power of the well operating mechanism for pulling upon the lever of the tongs, without winding the operating connection around a rotating drum as is the present practice. This usual method is objectionable, since serious injury may result from breaking of the flexible operating connection and the violent slapping of its loose end as it is rapidly wound on the drum.

in the present invention rotar I movement of the operating mechanism is converted to reciprocating movement, and an operating cable for the lever of the tongs is connected to the reciprocating member for movement therewith. By this arrangement the operating cable is not subject to a winding movement, and as a consequence breaking of the cable cannot result in dangerous swinging of its loose end.

it is a further object of the invention to convert a rotary drive to reciprocating movement by an eccentric and strap providing an extremely simple construction; and to readily engage or disengage the driving connection so that the tong operating means may remain stationary when not in use.

The invention will be readily understood from the following description of the accompanying drawings, in which:

Fig. 1 is a vertical section through a well derrick showing the tong operating mechanism in side elevation.

Fig. 2 is a front elevation of the tong operating means.

Figs. 3 and 4 are transverse sections on the lines 3-3 and 4- 1; of Fig. 2.

A well derrick is shown at 1, and is provided. with a frame 2 for the draw works of a rotary drill. The draw works is of usual construction including drum shaft 3 and main shaft 1, the latter having cat heads 5 keyed on the respective ends thereof as shown at 6. The table for the rotary drill is shown at 7, with drill stem 8 projecting upwardly therethrough and held by usual grippers 9. Shafts 3 and t and table 7 are rotated in usual manner by sprocket chains, the main drive chain being illustrated at 10, with. one of the sprockets on shaft 1 shown at 11.

Serial No. 25,004.

filhe joints of drill pipe 8 are set up or unscrewed by usual tongs 12 prov1ded with an operating lever 15, and the lever 1s swung by a cable connection let adapted to engage the eye in the end thereof. The cable is drawn tant for operating the tongs by means adapted to convert the rotary move" ment of sh aftf to reciprocating movement,

As an instance of this arrangement an ec centric 15 is journaled on shaft 4- adjacent one of the cat heads 5, andis adapted for axial shifting on the shaft by a yoke 16 engaging a grooved sleeve 17 which is integral with the eccentric. The confronting ends of the eccentric and the cat head form cooperating clutch elements 1819, so that shifting of the eccentric through the movement of yoke 16, will engage or disengage the clutch. With the clutch engaged, the eccentric rotates with the cat head 5 and the shaft 41, while disengagement of the clutch permits rotation of the draw works with the eccentric remaining stationary.

A two-piece strap 20, bolted together as shown at 21, is mounted on the periphery of the eccentric so that rotation thereof will reciprocate the strap without rotation of the same; and the cable 14 is fixed to the strap so that reciprocation of the latter will exert a pull upon the cable for operating the le ver of tongs 12. v

The rotary movement of shaft 4 is thus utilized for exerting a pull upon cable 14, without the necessity of winding the cable around cat head 5, and as a consequence accidental breaking of the cable will cause no injury, since its loose end will not be violent ly whipped around by the winding thereof on a rotating element of the mechanism.

An operating connection is provided for yoke 16 in order to conveniently engage or disengage clutch 1819, said operating connection comprising a link 22 slidable across the frame 2 and connected to the lever 23 which controls yoke 16. Link 22 is preferably shifted by a handle 24- connected thereto by a bell crank lever 2t.

Yoke 16 is normally shifted and held in position for disengagement of clutch elements 1819, by a spring 26 which preferably connects link 22 and the frame 2. As a consequence the mechanism for operating cable 1% normally remains stationary irrespective of operation of the draw works, and the clutch 1819 is engaged for operation a means only during the time that handle 2a is held in low-cred position, the spring 9-6 disengaging the clutch and thereby returning the operating nnarhanism to stationary position as soon as the handle is released.

We claim:

1. The cm'i'ibiinition with the draw works of a well which includes drive shaft and a cat head fixed on the end thereof, an axially shift-able eccentric 'journaled on the drive shaft adjacent the cat head, the proximate ends of the cat head and. eccentric forming cooperating clutch elements, the opposite end of the eccentric having a proyectmg sleeve provided with an annular recess, a forked operating arm engaging said recess for axially shifting the eccentric to engage or disengage the clutch, actuating means for the forked arm having an operating handle at the opposite end of the drive shaft, a strap on the eccentric, and a cable fixed to the strap and having means for engaging tongs.

2. The combination with the draw works of a well which includes a drive shaft and a cat head fixed thereon, of an axially shiftable member for converting rotary to reciprocating motion journaled on the drive shaft adjacent the cat head, means connected to the reciprocating element of said axially shiftable member for engaging tongs, the proximate ends of the cat head and axially shiftablc member forming cooperating clutch elements, and an operating connection, the opposite end of the axially shiftable member being adapted for engagement by said operating connection to axially shift said member for engaging or disengaging the clutch.

3. The combination with the draw works of awell which includes a drive shaft and a cat head fixed thereon, of an axially shiftable member for converting rotary to reci rocating motion journaled on the drive shaft adjacent the cat head, means connected of the cable actuatino to the reciprocating element of said axially shiftable member for engaging tongs, the proximate ends of the cat head and axially shiftable member forn'iing cooperating clutch elements, and means for moving the axially shiftable member to engage or disengage the clutch.

i. The combination of a cathead, means for rotating the cathead, a member adapted to convert rotary to reciprocating move ment, a driving connection between the cathead and said member axially shiftable for engaging or disengaging the driving con nection, and means connected to the recip' rocating element of the member for engag ing tongs.

The con'ibination of a cathead, means for rotating the cathead, means for converting rotary to reciprocating movement, a driving connection between said movement converting means and the cathead adapted for engagement or disengagement by relative axial movement between said movement converting iii-cans and the cathead, and means for engaging tongs connected to the reciprocating element of the movement convetting means.

The combination of a cathead, means for rotating the cathead, means for con verting rotary to reciprocating movement, a driving connection between said movement converting means and the cathead adapted for engagement by relative axial movement between said movement converting means and the cathead, yicldable tensioning means tending to cause relative axial movement between the movement converting means and the cathead in the opposite direction for disengaging the driving connection, and means for engaging tongs connected to the reciprocating element of the movement converting means.

In testimony whereof we have atlixed our signatures to this specification.

CECIL H. SWVEET. WELDON C. ERlVIN. 

